TRIFID^. 207 



Meldola, has the series of black clots along the costal margin 

 doubled, so as to be very closely and regularly ornamented 

 with sharp black spots ; among these is one of an otherwise 

 unicolorous green, and another equally devoid of black 

 lines, but of a buff colour. Mr. E. Adkin has a singular 

 form, obtained from Cork in the South of Ireland, almost 

 unicolorous dull greenish-slate, with the markings only 

 faintly indicated ; also others somewhat similar from the 

 Scilly Isles, along with some more strongly marked, but 

 leaning toward the peculiar Cambridge form. It is time that 

 this curious local race should be mentioned, since it is 

 supposed by some to be a distinct species, and has been 

 commonly recorded under the names of par (which belongs 

 to another variety) and impar (which was simply a joke). It 

 has rather a robust appearance, especially in some examples, 

 and in a few the base of the fore wings seems slightly 

 narrower, so as to give them a more triangular form • 

 the ground colour often shows no trace of green, but is 

 white, greyish-white, or brownish-white ; the markings more 

 obscure, cloudy, or shaded off, and the whole surface dusted 

 with grey or clouded with black. This form is found year by 

 year upon the walls of the colleges at Cambridge University, 

 and on houses in that city, and is very rarely mixed with 

 normal specimens ; on the other hand, the variation in coast 

 specimens extends so as to unite with and include this ; 

 indeed individuals inseparable from the Cambridge specimens 

 have been taken at Deal. It is difficult to do justice to the 

 endless variations of a species like this. 



On the wing in July and August, and occasionally into 

 September. 



Larva smooth and soft, rather limp, slightly thickest in 

 the middle, head smaller than the second segment, prominent, 

 shining, deep black, with the mouth white and rather hairy • 

 body rather flattened above and below ; green or smoky - 

 green or grey-green, the raised dots shining, almost metallic, 



